1. Field of the Invention
The present invention is related to apparatus monitoring systems and, more particularly, to gauge alert systems for monitoring apparatuses and notifying responsible individuals of the occurrence of predetermined alert conditions in the apparatuses.
2. Description of the Related Art
Large liquid fuel tanks, such as propane tanks (or more generally pressure vessels), typically include a measuring device and a gauge, so that operators can monitor the fuel level in the tank during operation and filling. The gauge can be, for example, a pressure gauge or a fluid level gauge. As large liquid fuel tanks are filled, it is common for the operator to perform other tasks or become otherwise distracted because of the relatively long period of time it takes such a tank to fill. If the operator over fills the tank, safe pressure limits can be exceeded. Further, the fuel supplies in these tanks last for long periods of time on the order of thirty or more days. Thus, there is a tendency for operators to forget to check the gauges thereby allowing the fuel tanks to be emptied.
The present invention solves the problems mentioned above and provides a distinct advance in the state of the art. In particular, the invention is directed to a gauge alert system with an output device, a sensor, a transmitter, a receiver, and an alert device. Upon occurrence of a predetermined alarm condition, the transmitter sends a signal to the receiver which in turn sends an alert activation signal to the alert device. When the alert device receives the signal, the alert device generates a user notification signal. Preferably, the gauge alert system is wireless, and the alarm signal comprises a wireless alarm signal.
In a preferred wireless gauge alert system, the output device is a fuel level detector for a liquid fuel tank. The output device includes a magnetic output member, and the sensor is a magnetic sensor operatively positioned relative to other output member to detect an output corresponding to the predetermined alert condition. Preferably, two sensors are provided with one sensor detecting a near empty status, and the other sensor detecting a near full status. So that the responsible individual knows which sensor has been activated, the wireless alarm signal sent by the transmitter is preferably encoded with a selected one of a plurality of codes corresponding to the activated sensor. Alternatively, the output device includes a variable resistance gauge, with a sensor detecting the resistance. The resistance is then converted to the fuel level of the vessel, preferably in terms of a percentage.
In an alternate embodiment, the output device is a fuel pressure sensor, operatively connected with either a magnetic output member or a variable resistance gauge. In this embodiment, the magnetic sensors or variable resistance sensors are set to detect predetermined pressure settings such that the sensors can alert the owner or service personnel of a potential critical failure such as propane relief valves expelling gas when overfilled, pumps running dry, and failure of other devices.
The preferred alert system includes a receiver unit held in a housing having a plug protruding therefrom to mount the receiver unit to an electrical socket in a high traffic area of a home, for example. The alert device preferably comprises a LED, and a reset switch is provided to turn the LED off. Alternatively, the receiver unit is mobile so that it can be mounted on a fuel delivery truck, other vehicle, or be worn on the person of a deliveryman that is responsible for the safe fuel level of the apparatus. The mobility of the alert device is particularly advantageous in construction and mining environments.
The alert system is also incorporated into computer monitoring embodiment. In this alternative, a receiver unit is combined with a personal computer (PC) or any other computer which receives the wireless signals. As incorporated into a home PC, the computer alerts the user of fuel levels and/or alert conditions allowing the user to respond accordingly. Alternatively, as incorporated into a vendor PC, the computer at the vendor""s place of business receives fuel level indicators and/or alert condition indicators allowing the vendor to respond accordingly such as automatically scheduling a refilling.
In an alternate wireless gauge alert system, multiple remote assemblies are provided for use in separate zones. Each zone remote assembly includes at least one sensor and a transmitter operable to transmit an encoded wireless alarm signal encoded with the zone from which the signal originated and the sensor which was activated in that zone. A receiver unit receives the wireless signal, and an alert device, preferably having a display, informs a responsible individual of the type of alert condition and the zone in which it occurred. For some applications, the alert device preferably comprises an auto dialer.